Sökning: "demagnetization"

Visar resultat 16 - 20 av 28 avhandlingar innehållade ordet demagnetization.

1. 16. Design and Evaluation of a Compact 15 kW PM Integral Motor

   Författare :Peter Thelin; KTH; []
   Nyckelord :integral motor; integrated motor drive; PM motor; PMSM; compact motor; filter coil; airgap flux density; axial leakage;

   Sammanfattning : This thesis deals with the integral motor of tomorrow, and particularly with a variable speed, sensorless permanent magnet synchronous motor with an integrated converter. The rated power is 15 kW at 1500 r/min. The outer dimensions are approximately the same as for the equivalent standard induction motor.Control strategies for pumps and fans, i. LÄS MER

3. 17. Effect of Dielectric and Magnetic Material Characteristics on Frequency Response of Power Transformers

   Författare :Nilanga Abeywickrama; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency response analysis; dielectric insulation; Complex permeability; core magnetization; finite element method; transformer diagnosis.; high frequency modelling; magnetic viscosity; silicon steel;

   Sammanfattning : Frequency response analysis (FRA) technique has become increasingly popular for the assessment of mechanicalintegrity in power transformers. This method is based on the fact that the shape of the frequency response at higher frequencies is uniquely determined by the geometrical construction of the transformer. LÄS MER

4. 18. Frequency comb Brillouin microscopy

   Författare :Felipe Ademir Alemán Hérnandez; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Brillouin light scattering; optics; spinwave spectroscopy; phonon spectroscopy; microscopy; Fabry-Perot interferometer; Frequency comb;

   Sammanfattning : Brillouin light scattering (BLS), an almost a century-old technique, has evolved into a powerful and versatile method to study acoustic and magnetic phenomena down to the nanometer size scale. Presently, BLS can be applied in fields as diverse as acoustics, spintronics, geosciences, and biophysics. LÄS MER

5. 19. Dynamics in magnetic metamaterials

   Författare :Agnė Čiučiulkaitė; Vassilios Kapaklis; Gabriella Andersson; Björgvin Hjörvarsson; Will Branford; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Metamaterials are artificially created structures with properties that are not found in nature. They can be tailored to achieve desired response to external excitations such as external electric and magnetic fields, as well as to enhance materials’ optical or magnetic activity. LÄS MER

7. 20. Theoretical methods for the electronic structure and magnetism of strongly correlated materials

   Författare :Inka L. M. Locht; Igor Di Marco; Silke Biermann; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dynamical mean field theory DMFT ; Hubbard I approximation; strongly correlated systems; rare earths; lanthanides; photoemission spectra; ultrafast magnetization dynamics; analytic continuation; Padé approximant method; two-particle Green s functions; linear muffin tin orbitals LMTO ; density functional theory DFT ; cerium; stacking fault energy.; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : In this work we study the interesting physics of the rare earths, and the microscopic state after ultrafast magnetization dynamics in iron. Moreover, this work covers the development, examination and application of several methods used in solid state physics. The first and the last part are related to strongly correlated electrons. LÄS MER